Is it rude if your homeroom teacher said this?

You should report it to the principle. Wow cares if people call you a tattle tail, your teacher is going to get her a** whooped. And if she doesn't, tell your parents. They can then threaten to sue if you don't get an apology from the teacher. Schools hate lawsuits! So pick your poison. Either way your teacher is going to get a slap in the wrist.